Spinal Perimedullary Arteriovenous Fistula Research Articles

Spontaneous obliteration of a spinal perimedullary fistula.

We herewith report a young patient who had an incidental spinal vascular malformation of the cervicomedullary junction discovered during a work-up for anosmia. Angiography demonstrated a perimedullary spinal arteriovenous fistula with supply from lateral spinal arteries arising from bilateral V3 level segmental arteries. It was decided to manage the patient conservatively with magnetic resonance imaging monitored biannually. On a recent follow-up magnetic resonance, nearly 10 years later, we noted a subtle change in caliber and imaging characteristics at the posterior margin of the cervical medullary junction. Repeat digital-subtraction angiography showed no evidence of early venous filling from the previously involved branches. Microcatheter exploration of the right lateral spinal artery confirmed spontaneous occlusion of the spinal perimedullary arteriovenous fistula, without any persistent shunting. Spontaneous resolution of a spinal vascular malformation is rare; this case demonstrates the dynamic nature of shunting vascular malformations and that spontaneous obliteration of arteriovenous shunts is possible.

Feasibility of Noninvasive Diagnosis of Spinal Vascular Diseases Using Time-Resolved Angiography With Stochastic Trajectories.

Background and Purpose: To determine the feasibility of time-resolved angiography with stochastic trajectories (TWIST) in the diagnosis of spinal dural arteriovenous fistula (SDAVF) and perimedullary arteriovenous fistula (PAVF).Methods: A total of 11 negative patients with TWIST examination were retrospective analyzed and then 18 patients with suspected spinal vascular diseases underwent TWIST. For negative patients, Adamkiewicz artery (AKA), great anterior radiculomedullary vein (GARV) and anterior spinal artery (ASA) were retrospective analyzed. In patients, the results of TWIST were compared with those of DSA.Results: The displaying rates of the ASA, AKA and GARV in 11 negative patients were 100, 90.9, and 90.9%, respectively. The AKA and GARV were separated on TWIST. Of 18 patients, 11 and three were diagnosed with SDAVF and PAVF, respectively. The spinal cord vascular malformation diagnosed on TWIST was consistent with DSA with an excellent intermodality agreement (Kappa = 0.92, p < 0.001). The feeding artery and side of all 11 SDAVF patients were displayed on TWIST and the results were consistent with DSA. For PAVF patients, the feeding artery in two patients and the sides as displayed on TWIST were consistent with DSA.Conclusions: TWIST enables the differentiation of the spinal artery and vein and the differential diagnosis of SDAVF and PAVF.

Pediatric perimedullary arteriovenous fistula: clinical features and endovascular treatments

ObjectivePediatric spinal perimedullary arteriovenous fistula (PMAVF) is rare but may cause permanent disability. We aim to summarize the clinical features of pediatric PMAVFs and our clinical experience in their treatment...

Study and therapeutic progress on spinal cord perimedullary arteriovenous fistulas.

Spinal cord perimedullary arteriovenous fistulas (PMAVFs) are rare and belong to type IV spinal cord arteriovenous malformations (AVMs). Little is known regarding the treatment and prognosis of spinal cord PMAVFs. In the present study the relevant literature from PubMed was reviewed, and it was found that these fistulas can occur at all ages but are more common in children. In children, most spinal cord PMAVFs are large and with high flow, begin with bleeding and are frequently associated with hereditary hemorrhagic telangiectasia. However, in adults, most spinal cord PMAVFs are small and with low flow and begin with progressive spinal cord dysfunction. The early diagnosis of spinal cord PMAVFs is generally difficult, and symptoms can be very severe at the time of diagnosis. Digital subtraction angiography remains the gold standard; however, computed tomography angiography and magnetic resonance angiography are also promising. Spinal cord PMAVFs can be treated by endovascular embolization, surgical removal or a combination of the two methods. Most spinal cord PMAVFs show good outcomes after the appropriate treatment, and the prognosis is primarily associated with the blood flow of the PMAVF. For high-flow spinal cord PMAVFs, endovascular embolization is more effective and can lead to a good outcome; however, for low-flow spinal cord PMAVFs, surgical removal or the combination with endovascular embolization is the optimal choice. The prognosis for low-flow types is slightly worse than for high-flow spinal cord PMAVFs in children, but the outcome is acceptable.

Spontaneous resolution of syringohydromyelia in a case of spinal Perimedullary Arteriovenous fistula (Type IVA) associated with low lying tethered cord

Spontaneous resolution of syringohydromyelia in a case of spinal Perimedullary Arteriovenous fistula (Type IVA) associated with low lying tethered cord

Influence of indocyanine green angiography on microsurgical treatment of spinal perimedullary arteriovenous fistulas

The microvascular anatomy of spinal perimedullary arteriovenous fistulas (AVFs) is more complicated than that of dural AVFs, and occlusion rates of AVF after open microsurgery or endovascular embolization are lower in patients with perimedullary AVFs (29%-70%) than they are in those with dural AVF (97%-98%). Reports of intraoperative blood flow assessment using indocyanine green (ICG) video angiography in spinal arteriovenous lesions have mostly been for spinal dural AVFs. No detailed reports on spinal perimedullary AVFs are available. Participants were 11 patients with spinal perimedullary AVFs (Type IVa in 5 patients, Type VIb in 4, and Type IVc in 2). Intraoperative ICG video angiography was assessed by measuring the number of cases in which this modality was judged essential by the surgeon to correctly occlude the fistula. In all patients, arterial feeders were identified and intravenous ICG video angiography was performed before and after blocking the feeders. In one patient, selective intraarterial ICG video angiography was also performed. The findings provided by ICG video angiography significantly changed the surgical procedure in 4 of 11 patients (36%). Postoperatively, complete occlusion of the AVF was achieved in 10 of the 11 patients (91%). Intraoperative ICG video angiography can have a significant impact on deciding surgical strategy in the microsurgical treatment of spinal perimedullary AVF.

MRI findings of spinal arteriovenous fistulas: focusing on localisation of fistulas and differentiation between spinal dural and perimedullary arteriovenous fistulas

To investigate the magnetic resonance imaging (MRI) findings of spinal arteriovenous fistulas (AVFs) to predict their locations and types. Patients who underwent spinal angiography for suspected spinal AVF between April 2003 and April 2013 were enrolled. Spine MRI images were analysed by two radiologists in consensus focusing on the distribution patterns of flow void pial vessels (FVPVs): longitudinal distribution pattern along the spinal level (even or uneven, with description of the most crowded level in uneven cases) and axial distribution pattern in relation to the cord (ventral, dorsal, or co-dominance). Spinal angiography served as the reference standard for the locations and types of fistulas. Thirty-two patients (M:F=24:8, mean age, 53 years; range, 2-74 years) were included. There were 18 patients with spinal dural AVFs (SDAVFs), seven with perimedullary AVFs, four with epidural AVFs, and three diagnosed as normal. In 12 of 15 longitudinally uneven AVFs, the most crowded levels of FVPVs corresponded to the true fistulous levels within two-level differences. While dorsal dominance was predominant in SDAVFs (13/18), ventral dominance was predominant in perimedullary AVFs (5/7; p<0.01). Fistulous levels may be predicted to be within two levels of the most crowded levels of FVPVs. The dorsal dominance pattern of FVPVs favours SDAVFs, whereas ventral dominance suggests perimedullary AVFs.

Endovascular Treatment of Spinal Vascular Lesion in Japan: Japanese Registry of Neuroendovascular Therapy (JR-NET) and JR-NET2

A subgroup analysis of spinal vascular lesions in the Japanese Registry of Neuroendovascular Therapy (JR-NET) and JR-NET2, retrospective registry studies conducted in 2005–2009, was performed to understand the current status of treatment in Japan. Of 201 spinal lesions enrolled, 98 analyzable cases of spinal dural arteriovenous fistula (SDAVF), 43 of spinal perimedullary arteriovenous fistula (SPAVF), and 23 of spinal intramedullary arteriovenous malformation (SIAVM) were assessed. Treatment was radical in the majority (83.6%) of SDAVF, palliative in the majority (70.6%) of SIAVM, and radical and palliative in a similar number of cases of SPAVF. Total occlusion was achieved in 26 (54.2%) SDAVF cases, 9 (29.0%) SPAVF, and 4 (23.5%) SIAVM. Treatment-related complications occurred in 3 (3.1%) SDAVF cases, 7 (16.3%) SPAVF, and 1 (4.3%) SIAVM. Post-treatment neurological improvement was achieved in 49 (50.0%) of SDAVF cases, 15 (34.9%) SPAVF, and 5 (21.7%) SIAVM. The modified Rankin Scale (mRS) of 0, 1, or 2 on postoperative day 30, the primary endpoint, was achieved in 62 (63.3%) SDAVF cases, 26 (60.5%) SPAVF, and 12 (52.2%) SIAVM. The mRS of 0–2 on postoperative day 30 was correlated with pre-symptomatic mRS of 0–2 [P < 0.0001, odds ratio (OR): 42.88, 95% confidence interval (CI): 14.83–123.97] and postoperative neurological improvement (P = 0.046, OR: 2.57, 95% CI: 1.02–6.48). In Japan, endovascular treatment of spinal vascular lesions was administered safely. Good mRS on postoperative day 30 was highly correlated with good pre-symptomatic mRS, suggesting necessity of early diagnosis and treatment.

Traumatic spinal perimedullary arteriovenous fistula due to knife stabbing and subsequent kyphosis

Perimedullary arteriovenous fistula (AVF) is a relatively rare spinal vascular malformation. Although it has traditionally been considered to be a congenital lesion, some cases identified in adults have suggested that the lesion may be acquired. The etiology and exact mechanism of these lesions are unknown. The authors present a case of a perimedullary AVF caused by a direct stabbing injury of the spinal cord and induced by subsequent kyphosis, and they discuss the pathogenesis and treatment strategy.

Spontaneous Thrombosis of a Spinal Conus Perimedullary Arteriovenous Fistula

A 49-year-old male presented with a rare case of acute lower extremity paresis caused by spontaneous thrombosis of a spinal conus perimedullary arteriovenous fistula (AVF) after a subacute myelopathic course. Magnetic resonance imaging obtained after deterioration showed that the flow voids around the conus medullaris had changed from hypointense to hyperintense lesions. Surgery with thoracic laminoplasty was performed to determine the nature of the lesion because angiography was negative. During surgery, thrombosed abnormal vessels were observed, consistent with thrombosis of a spinal conus perimedullary AVF. Histological specimens of the thrombosed vessels exhibited vascular wall injury such as intimal alteration, wall dissection, and mural thrombus. Hemorrhage and infection were excluded. Vascular wall injury of draining veins and varices were probably one of the causes of thrombosis in the present case. Spinal arteriovenous malformation generally causes progressive venous congestive myelopathy, but the congestive myelopathy may rarely rapidly deteriorate with spontaneous thrombosis, known as Foix and Alajouanine syndrome.

Endovascular embolization for symptomatic perimedullary AVF and intramedullary AVM: a series and a literature review

Perimedullary arteriovenous fistula (AVF) has shunt on the spinal cord surface and it can be treated with surgery, or endovascular embolization. Intramedullary arteriovenous malformation (AVM) has its nidus in the cord and is difficult to treat either by surgery or endovascular technique. We report our experience with endovascular embolization in the treatment of perimedullary AVF and intramedullary AVM. Four consecutive cases of spinal perimedullary AVF and six intramedullary AVM were retrospectively reviewed. These cases were evaluated and treated at Beijing Tiantan Hospital, China, over a 2-year period. A review of previously reported cases was also performed. There was no significant difference in the presentations (P = 0.348), level of lesions (P = 0.350), arterial suppliers (P = 0.801), and associated vascular anomalies between perimedullary AVF and intramedullary AVM, except for age (P = 0.014) and treatment modalities (P = 0.003). The patients with perimedullary AVFs were younger in our cases; the age at onset of symptoms averaged 25.8 years compared to 31.7 years for intramedullary AVMs. There was a significant male predominance for both lesions, and a significantly higher incidence of subarachnoid hemorrhage than in spinal dural AVFs. Regarding treatment, endovascular coil embolization is frequently used in perimedullary AVF and liquid embolic agent is an effective therapeutic choice in intramedullary AVM. Perimedullary AVF and intramedullary AVM are dissimilar with dural AVF in clinical characteristics. Our experience suggests that the endovascular treatment of spine perimedullary AVFs and intramedullary AVMs is feasible and effective. Endovascular treatment for intramedullary AVMs is still challenging, the main problem is acute ischemia injury of the spinal cord.

Effectiveness of intraoperative near-infrared indocyanine green videoangiography in a case with recurrent spinal perimedullary arteriovenous fistula

Flow measurement by microvascular ultrasonic flow probe is an established procedure in intracranial vascular surgery. This study tested the application of this procedure in spinal dural arteriovenous fistula (SDAVF) treatment.Data from 12 SDAVF patients who consecutively underwent microsurgical resection with the assistance of both microflow probe and indocyanine green videoangiography (ICG-VA) were retrospectively analyzed. Flowmetry was performed on a dilated perimedullary venous plexus at different distances from the fistula point (FP). In addition, measurements were made at different phases of surgery to address specific issues: at the beginning, to identify the fistula; after temporary clipping, to evaluate proper disconnection; and after section, to exclude residual filling.Flowmetry was reliable in assessing both the value and direction of flow in all cases, thereby aiding fistula localization and confirming its disconnection. Indeed, fistula localization was helped by detection of increasing flow values approaching the FP (mean flow: 11 mL/min <10 mm vs. 3 mL/min >20 mm), while fistula disconnection was confirmed by a flow value lower than 1 mL/min (0–1 mL/min). Data from microflow probe measurements were concordant with ICG-VA data in all cases. In 3 cases, ICG-VA findings on fistula disconnection uncertain due to residual ICG dye were clarified by flowmetry.With the limits of our small series, multistage intraoperative quantitative flow measurement is a feasible, safe, and reliable adjunct in the surgical treatment of SDAVFs. The procedure provides data helpful in guiding the surgical strategy or clarifying ICG-VA data when necessary.

The endovascular treatment of a spinal perimedullary arteriovenous fistula with coils: a case report

We report a case of direct spinal intradural ventral arteriovenous fistula of the thoraco-lumbar region. Angiography demonstrated a single feeder from the anterior spinal artery that drained directly into a...

Traumatic spinal perimedullary arteriovenous fistula: a case report

Spinal perimedullary arteriovenous fistula, a subtype of spinal arteriovenous malformation, is generally considered to be a congenital lesion by maldevelopment of the spinal vascular system. However, several cases of perimedullary arteriovenous fistula had been reported in the literature, which were thought to be acquired lesions. We presented a case of perimedullary arteriovenous fistula, which was believed to be derived from spinal cord trauma. The etiology and pathophysiology of this case were discussed, and it might provide further insight into the pathogenesis of such lesions.

A Transmedullary Approach to Occlusion of a Ventral Perimedullary Arteriovenous Fistula of the Thoracic Spinal Cord

A spinal perimedullary arteriovenous fistula (PMAVF) is a direct fistula of one or more spinal arteries into the perimedullary venous network with reversed venous flow and subsequent venous congestion of the spinal cord. The therapeutic goal of surgery is to normalize the venous drainage by obliterating the fistula. Strictly ventral lesions typically require an anterior approach to ensure adequate exposure of the fistula as well and the preservation of the physiological blood supply to the spinal cord. We present a case of a ventral PMAVF at the level of T10 with feeders from the anterior spinal artery, caudally draining veins on the ventral spinal cord, and a dilated transmedullary vein filling cranially draining veins on the dorsal aspect of the spinal cord. The dilated transmedullary vein was approached by a laminectomy. The vein was coagulated, and the gliotic channel was used to approach the ventral fistula site from the dorsal surface of the spinal cord. Complete obliteration of the fistula was achieved, and the preoperative neurological deficit improved. We conclude that transmedullarly draining veins offers a possible dorsal approach for the occlusion of some ventral PMAVFs, thus avoiding more complex anterior approaches to the ventral spinal cord.

Intracranial Pial Arteriovenous Fistulas

Intracranial pial arteriovenous fistula (AVF) is a rare cerebrovascular lesion that has only recently been recognized as a distinct pathological entity. A 41-year-old woman (Patient 1) presented with the sudden development of an altered mental state. Brain CT showed an acute subdural hematoma. A red sylvian vein was found intraoperatively. A pial AVF was revealed on postoperative angiography, and surgical disconnection of the AVF was performed. A 10-year-old boy (Patient 2) presented with a 10-day history of paraparesis and urinary incontinence. Brain, spinal MRI and angiography revealed an intracranial pial AVF and a spinal perimedullary AVF. Endovascular embolization was performed for both lesions. The AVFs were completely obliterated in both patients. On follow-up, patient 1 reported having no difficulty in performing activities of daily living. Patient 2 is currently able to walk without assistance and voids into a diaper. Intracranial pial AVF is a rare disease entity that can be treated with surgical disconnection or endovascular embolization. It is important for the appropriate treatment strategy to be selected on the basis of patientspecific and lesion-specific factors in order to achieve good outcomes.

Spinal aneurysm arising from the feeding pedicle of a thoracic perimedullary arteriovenous fistula: case report

Background Aneurysms of the spinal artery are exceedingly rare. We report on the first case of a pathologically proven aneurysm arising from the feeding pedicle of a perimedullary arteriovenous fistula (AVF). Case Description A 42-year-old man presented with subarachnoid hemorrhage (SAH) and spinal angiography demonstrated a thoracic perimedullary AVF fed by the left T8 intercostal artery that also harbored a spinal aneurysm. He underwent laminectomy 18 days postonset. The aneurysm was resected and the fistula was interrupted. Conclusion For appropriate treatment planning, it is necessary to rule out the presence of aneurysms on the feeding vessel in patients with spinal perimedullary AVF who present with SAH.

頭蓋頚椎移行部動静脈ろうの検討

We report 6 patients with rare arteriovenous fistulas of the craniocervical junction: 5 men and 1 woman ranging in age from 54 to 75 years. All manifested associated subarachnoid hemorrhage. Angiography demonstrated that 4 of the 6 fistulas were spinal dural arteriovenous fistulas (SDAVF) fed by the meningeal branch of the vertebral artery, the other 2 were spinal perimedullary arteriovenous fistulas (SPAVF) fed by the anterior spinal artery. Drainage was via the perimedullary vein of the craniocervical junction. Retrograde leptomeningeal venous drainage (RLVD) into the intracranial venous system was recognized in 5 cases; in 3 the draining system contained varices. All 6 patients underwent direct surgery using the transcondylar fossa approach. Before proceeding to surgical coagulation, intraoperative angiography proved useful for the temporary clipping to the feeding artery in our SPAVF cases or the drainer in the SDAVF cases. The postoperative course of 5 patients was good; the other patient remained moderately disabled due to initial damage of the medulla oblongata. SPAVF and SDAVF in the craniocervical junction led to subarachnoid hemorrhage and the presence of RLVD into the intracranial venous system was related to the hemorrhagic symptoms. By direct surgery a good prognosis can be achieved in patients with arteriovenous fistulas of the craniocervical junction.

Spinal giant intradural perimedullary arteriovenous fistula: Clinical and neuroradiological study in one case with review of literature

Giant intradural perimedullary arteriovenous fistula with massive spinal cord compression is rare. The therapeutic difficulties include whether endovascular embolization or direct surgical excision should be selected. We present a patient with the largest giant spinal intradural perimedullary arteriovenous fistula shown by magnetic resonance imaging so far reported, who was successfully treated by a combination of endovascular embolization and direct surgery. A 16-year-old girl presented with a giant intradural arteriovenous fistula (perimedullary Type II) at the C4-5 level, manifesting as progressive cervical myeloradiculopathy. The single-hole fistula was supplied by the anterior spinal artery and an ascending artery arising from both the costocervical and highest intercostal arteries with a rapid transit time, and drained superiorly to the foramen magnum, and inferiorly to the thoracic spinal canal, through a huge venous lake at the site of the arteriovenous connection. The patient was treated by transarterial embolization with platinum coils and silk, followed by surgical excision with excellent results at 12 months' follow-up. We recommend that such a huge perimedullary arteriovenous fistula with a rapid transit time, and severe cord and root compression, should be treated with embolization followed by surgical excision.